Adjustments to oven temperature, baking time, pan selection, and pan preparation can significantly affect the outcome of high-altitude baking. Here are tips for manipulating these factors at high altitude, plus notes on storage.

Baking pans/Pan preparation

Always use pan sizes specified in your recipe; since baked goods rise markedly at high altitude, they may over-rise and spill into the oven if baked in a pan that's too small. Substituting a tube pan for a loaf or round pan will bring heat to the batter's center, usually resulting in a better rise and quicker set, especially for dense, fruited cakes. You can make your own tube pan by taking a round cake pan and placing a metal "cake tube"sold for this purpose at bakeware shopsor an overturned one-cup metal measuring cup (without handle) in the center.

At high altitude, cakes tend to stick to pans, but this can be easily prevented. Up to 5,000 feet, it's sufficient to grease and flour pans, but if you're above that altitude, grease pan, line with parchment or wax paper, then grease and flour the paper. When baking cookies, it's best to use single-layer cookie sheets; insulated, double-layer pans reduce surface heat and prevent crisping. Prepare muffin pans by coating with shortening or nonstick vegetable spray. At 9,000 feet and above, muffins tend to stick even more so grease and flour pans or line them with paper or foil muffin cups.

Baking temperatures and times

At high altitude it's critical to completely preheat your ovengive it at least 15 minutesbecause you need to get all the heat you can from it. Use an auxiliary thermometer inside the oven to make sure the temperature is correct. Oven rack placement is equally important: The hottest position is at the bottom (closest to the heat source); the middle rack delivers moderate, even heat.

From 5,000 feet to 7,000 feet, baking is often improved by raising the oven temperature 15°F to 25°F because the extra heat quickly sets the batter's cell structure. Between 7,000 feet and 9,000 feet, raising the temperature can sometimes cause over-crusting on the surface of baked goods. Instead, it's best to use a moderate heat and increase the baking time. At 9,000 feet and above, preheat oven about 25 degrees above the baking temperature called for in the recipe. As soon as the baked goods are placed inside the oven, lower the heat to the actual baking temperature called for in the recipe.

Storing Baked Goods

At high altitude, baked goods dry out and get stale quickly. As soon as they are completely cool, wrap them in airtight plastic wrap or sealable plastic bags. For long storage, double-wrap in airtight plastic, then cover with heavy-duty foil or place in heavy-duty freezer bags.